For example, JP-A-2004-252563, JP-A-2006-33377 disclose a configuration including a cellular phone device and a vehicular device. The cellular phone device is configured to implement near-field wireless communications and carried in a vehicle interior. The vehicular device is equipped in the vehicle and also configured to implement near-field wireless communications. When the cellular phone device carried in the vehicle interior is communicable with the vehicular device via the near-field wireless communications, connection of an e-mail data transfer protocol is made between the cellular phone device and the vehicular device for transmission of e-mail data. Thereby, near-field wireless communications are enabled between the cellular phone device and the vehicular device. At this time, a user manipulates the vehicular device to cause the cellular phone device to transfer the e-mail data stored in the cellular phone device to the in-vehicle device thereby to browse the e-mail data stored in the cellular phone device. Thus, the e-mail data stored in the vehicular device is updated with the e-mail data transferred from the cellular phone device.
It is noted that, in a time period in which e-mail data is transferred and in a time period in which e-mail data is updated, a user cannot read the e-mail data by manipulating the vehicular device. It is conceivable to employ a configuration in which an e-mail data transfer processing is implemented to transfer the e-mail data, each time when a cellular phone device and a vehicular device connect an e-mail data transfer protocol therebetween. In such a configuration, immediately after making the connection of the e-mail data transfer protocol, a user cannot read e-mail data. Consequently, sufficient operability cannot be produced. In addition, when a configuration is employed to transfer e-mail data via wireless communications, it is also conceivable to cause instantaneous disconnection (momentary disconnection) in the communication channel. Therefore, when a configuration is employed to implement an e-mail data transfer processing and an e-mail data update processing each time when the e-mail data transfer protocol is re-connected in response to the instantaneous disconnection, processing load may be increased unnecessarily.